ASTM E1226-00

Standard Test Method for Pressure and Rate of Pressure Rise for Combustible Dusts

SCOPE
1.1 This test method is designed to determine the deflagration parameters of a combustible dust-air mixture within a near-spherical closed vessel of 20 L or greater volume. The parameters measured are the maximum pressure and the maximum rate of pressure rise.
1.2 Data obtained from this test method provide a relative measure of deflagration characteristics. The data have also been shown to be applicable to the design of protective measures, such as deflagration venting (1).  
1.3 This test method should be used to measure and describe the properties of materials in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment that takes into account all of the factors that are pertinent to an assessment of the fire hazard of a particular end use. Note 1-The evaluation of the deflagration parameters of maximum pressure and maximum rate of pressure rise can also be done using a 1.2-L Hartmann Apparatus. Test Method E789, has been published regarding this application; however, the use of these data in the design of deflagration venting and containment systems is not recommended.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Mar-2000
• Technical Committee: E27 - Hazard Potential of Chemicals
• Drafting Committee: E27.05 - Explosibility and Ignitability of Dust Clouds

Standards Content (Sample)

Designation: E 1226 – 00
Standard Test Method for
1
Pressure and Rate of Pressure Rise for Combustible Dusts
This standard is issued under the fixed designation E 1226; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The primary objective for the laboratory determination of the dust deflagration index, K , the
St
maximum pressure, P , and the maximum rate of pressure rise, (dP/dt) , is the use of these values
max max
for the design of protection systems. These parameters provide a measure of the potential severity of
a deflagration of a combustible dust-air mixture. These parameters are a function of many factors, such
as the turbulence, concentration, and homogeneity of the dust-air mixture; the type, energy, and
location of the ignition source; the geometry of the test vessel; the particle size distribution of the dust;
and the initial temperature and pressure of the tested mixture. Therefore, it is necessary to develop a
standard laboratory test method, the data from which can be referenced against data from large-scale
testing. For information on the sizing of deflagration vents, see NFPA 68.
This test method describes procedures for explosibility testing of dusts in laboratory chambers that
have volumes of 20 L or greater. It is the purpose of this test method to provide information that can
be used to predict the effects of an industrial scale deflagration of a dust-air mixture without requiring
large-scale tests.
this application; however, the use of these data in the design of
1. Scope
deflagration venting and containment systems is not recommended.
1.1 This test method is designed to determine the deflagra-
1.4 This standard does not purport to address all of the
tion parameters of a combustible dust-air mixture within a
safety concerns, if any, associated with its use. It is the
near-spherical closed vessel of 20 L or greater volume. The
responsibility of the user of this standard to establish appro-
parameters measured are the maximum pressure and the
priate safety and health practices and determine the applica-
maximum rate of pressure rise.
bility of regulatory limitations prior to use.
1.2 Data obtained from this test method provide a relative
measure of deflagration characteristics. The data have also
2. Referenced Documents
been shown to be applicable to the design of protective
2
2.1 ASTM Standards:
measures, such as deflagration venting (1).
D 3173 Test Method for Moisture in the Analysis Sample of
1.3 This test method should be used to measure and describe
3
Coal and Coke
the properties of materials in response to heat and flame under
D 3175 Test Method for Volatile Matter in the Analysis
controlled laboratory conditions and should not be used to
3
Sample of Coal and Coke
describe or appraise the fire hazard or fire risk of materials,
E 789 Test Method for Pressure and Rate of Pressure Rise
products, or assemblies under actual fire conditions. However,
for Dust Explosions in a 1.2-Litre Closed Cylindrical
results of this test may be used as elements of a fire risk
4
Vessel
assessment that takes into account all of the factors that are
E 1515 Test Method for Minimum Explosible Concentra-
pertinent to an assessment of the fire hazard of a particular end
4
tion of Combustible Dusts
use.
2.2 NFPA Publication:
NOTE 1—The evaluation of the deflagration parameters of maximum 5
NFPA 68 Guide for Deflagration Venting
pressure and maximum rate of pressure rise can also be done using a 1.2-L
2.3 VDI Standard:
Hartmann Apparatus. Test Method E 789, has been published regarding
6
VDI-3673 Pressure Release of Dust Explosions
1
This test method is under the jurisdiction of ASTM Committee E-27 on Hazard
3
Potential of Chemicals and is the direct responsibility of Subcommittee E27.05 on Annual Book of ASTM Standards, Vol 05.05.
4
Dusts. Annual Book of ASTM Standards, Vol 14.02.
5
Current edition approved March 10, 2000. Published April 2000. Originally Available from National Fire Protection Association, Batterymarch Park,
e1
published as E 1226 – 88. Last previous edition E 1226 – 94 . Quincy, MA 02269.
2 6
The boldface numbers in parentheses refer to a list of references at the end of Available from Beuth Verlag, D-1000 Berlin, Federal Republic of Germany or
this test method. from American National Standards Institute, 1430 Broadway, NY, NY 10018.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
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E 1226
2.4 ISO Standard:
ISO 6184/1 Explosion Protection Systems, Part 1, Determi-
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nation of Explosion Indices of Combustible Dusts in Air
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 P —the maximum explosion pressure (above the
ex
pressu
...